<?php //$Id: backuplib.php,v 1.4 2006/01/13 03:45:30 mjollnir_ Exp $
	//This php script contains all the stuff to backup/restore
	//survey mods

	//This is the "graphical" structure of the survey mod:
	//													--------------------
	//						   survey				   | survey_questions |
	//						(CL,pk->id)				 |(CL,pk->id,?????) |
	//							|					   --------------------
	//							|
	//			 -----------------------------------		
	//			 |								 |
	//		survey_analysis				   survey_answers
	//	(UL,pk->id, fk->survey)		   (UL,pk->id, fk->survey)
	//
	// Meaning: pk->primary key field of the table
	//		  fk->foreign key to link with parent
	//		  nt->nested field (recursive data)
	//		  CL->course level info
	//		  UL->user level info
	//		  files->table may have files)
	//
	//-----------------------------------------------------------

	function survey_backup_mods($bf,$preferences) {

		global $CFG;

		$status = true;

		//Iterate over survey table
		$surveys = get_records ("survey","course",$preferences->backup_course,"id");
		if ($surveys) {
			foreach ($surveys as $survey) {
				if (backup_mod_selected($preferences,'survey',$survey->id)) {
					$status = survey_backup_one_mod($bf,$preferences,$survey);
				}
			}
		}
		return $status;
	}

	function survey_backup_one_mod($bf,$preferences,$survey) {
		
		$status = true;
		
		if (is_numeric($survey)) {
			$survey = get_record('survey','id',$survey);
		}
		
		//Start mod
		fwrite ($bf,start_tag("MOD",3,true));
		//Print choice data
		fwrite ($bf,full_tag("ID",4,false,$survey->id));
		fwrite ($bf,full_tag("MODTYPE",4,false,"survey"));
		fwrite ($bf,full_tag("TEMPLATE",4,false,$survey->template));
		fwrite ($bf,full_tag("DAYS",4,false,$survey->days));
		fwrite ($bf,full_tag("TIMECREATED",4,false,$survey->timecreated));
		fwrite ($bf,full_tag("TIMEMODIFIED",4,false,$survey->timemodified));
		fwrite ($bf,full_tag("NAME",4,false,$survey->name));
		fwrite ($bf,full_tag("INTRO",4,false,$survey->intro));
		fwrite ($bf,full_tag("QUESTIONS",4,false,$survey->questions));
		
		//if we've selected to backup users info, then execute backup_survey_answers and
		//backup_survey_analysis
		if (backup_userdata_selected($preferences,'survey',$survey->id)) {
			$status = backup_survey_answers($bf,$preferences,$survey->id);
			$status = backup_survey_analysis($bf,$preferences,$survey->id);
		}
		//End mod
		$status =fwrite ($bf,end_tag("MOD",3,true));
		return $status;
	}

	//Backup survey_answers contents (executed from survey_backup_mods)
	function backup_survey_answers ($bf,$preferences,$survey) {

		global $CFG;

		$status = true;

		$survey_answers = get_records("survey_answers","survey",$survey,"id");
		//If there is answers
		if ($survey_answers) {
			//Write start tag
			$status =fwrite ($bf,start_tag("ANSWERS",4,true));
			//Iterate over each answer
			foreach ($survey_answers as $sur_ans) {
				//Start answer
				$status =fwrite ($bf,start_tag("ANSWER",5,true));
				//Print survey_answers contents
				fwrite ($bf,full_tag("ID",6,false,$sur_ans->id));
				fwrite ($bf,full_tag("USERID",6,false,$sur_ans->userid));
				fwrite ($bf,full_tag("QUESTION",6,false,$sur_ans->question));
				fwrite ($bf,full_tag("TIME",6,false,$sur_ans->time));
				fwrite ($bf,full_tag("ANSWER1",6,false,$sur_ans->answer1));
				fwrite ($bf,full_tag("ANSWER2",6,false,$sur_ans->answer2));
				//End answer
				$status =fwrite ($bf,end_tag("ANSWER",5,true));
			}
			//Write end tag
			$status =fwrite ($bf,end_tag("ANSWERS",4,true));
		}
		return $status;
	}

	//Backup survey_analysis contents (executed from survey_backup_mods)
	function backup_survey_analysis ($bf,$preferences,$survey) {

		global $CFG;

		$status = true;

		$survey_analysis = get_records("survey_analysis","survey",$survey,"id");
		//If there is analysis
		if ($survey_analysis) {
			//Write start tag
			$status =fwrite ($bf,start_tag("ANALYSIS",4,true));
			//Iterate over each analysis
			foreach ($survey_analysis as $sur_ana) {
				//Start answer
				$status =fwrite ($bf,start_tag("ANALYS",5,true));
				//Print survey_analysis contents
				fwrite ($bf,full_tag("ID",6,false,$sur_ana->id));
				fwrite ($bf,full_tag("USERID",6,false,$sur_ana->userid));
				fwrite ($bf,full_tag("NOTES",6,false,$sur_ana->notes));
				//End answer
				$status =fwrite ($bf,end_tag("ANALYS",5,true));
			}
			//Write end tag
			$status =fwrite ($bf,end_tag("ANALYSIS",4,true));
		}
		return $status;
	}

	function survey_check_backup_mods_instances($instance,$backup_unique_code) {
		$info[$instance->id.'0'][0] = $instance->name;
		$info[$instance->id.'0'][1] = '';
		if (!empty($instance->userdata)) {
			  //Subscriptions
			$info[$instance->id.'1'][0] = get_string("answers","survey");
			if ($ids = survey_answer_ids_by_instance ($instance->id)) {
				$info[$instance->id.'1'][1] = count($ids);
			} else {
				$info[$instance->id.'1'][1] = 0;
			}
		}
		return $info;
	}


	////Return an array of info (name,value)
	function survey_check_backup_mods($course,$user_data=false,$backup_unique_code,$instances=null) {
		if (!empty($instances) && is_array($instances) && count($instances)) {
			$info = array();
			foreach ($instances as $id => $instance) {
				$info += survey_check_backup_mods_instances($instance,$backup_unique_code);
			}
			return $info;
		}
	   //First the course data
	   $info[0][0] = get_string("modulenameplural","survey");
	   if ($ids = survey_ids ($course)) {
		   $info[0][1] = count($ids);
	   } else {
		   $info[0][1] = 0;
	   }

		//Now, if requested, the user_data
		if ($user_data) {
			//Subscriptions
			$info[1][0] = get_string("answers","survey");
			if ($ids = survey_answer_ids_by_course ($course)) {
				$info[1][1] = count($ids);
			} else {
				$info[1][1] = 0;
			}
		}
		return $info;
	}

	//Return a content encoded to support interactivities linking. Every module
	//should have its own. They are called automatically from the backup procedure.
	function servey_encode_content_links ($content,$preferences) {

		global $CFG;

		$base = preg_quote($CFG->wwwroot,"/");

		//Link to the list of serveys
		$buscar="/(".$base."\/mod\/servey\/index.php\?id\=)([0-9]+)/";
		$result= preg_replace($buscar,'$@SURVEYINDEX*$2@$',$content);

		//Link to servey view by moduleid
		$buscar="/(".$base."\/mod\/servey\/view.php\?id\=)([0-9]+)/";
		$result= preg_replace($buscar,'$@SURVEYVIEWBYID*$2@$',$result);

		return $result;
	}

	// INTERNAL FUNCTIONS. BASED IN THE MOD STRUCTURE

	//Returns an array of surveys id
	function survey_ids ($course) {

		global $CFG;

		return get_records_sql ("SELECT a.id, a.course
								 FROM {$CFG->prefix}survey a
								 WHERE a.course = '$course'");
	}

	//Returns an array of survey answer id
	function survey_answer_ids_by_course ($course) {

		global $CFG;

		return get_records_sql ("SELECT s.id , s.survey
								 FROM {$CFG->prefix}survey_answers s,
									  {$CFG->prefix}survey a
								 WHERE a.course = '$course' AND
									   s.survey = a.id");
	}

	function survey_answer_ids_by_instance ($instanceid) {

		global $CFG;

		return get_records_sql ("SELECT s.id , s.survey
								 FROM {$CFG->prefix}survey_answers s
								 WHERE s.survey = $instanceid");
	}

?>
